Edit HTML code in the textarea on this page. You can always use your right mouse button or Ctrl+v to paste code from your clipboard to the textarea. In some browsers just draw your file to the textarea to load your code or select your file with this button.
You can always copy the code in the textarea to a text editor like Notepad and save it as a file when you are pleased with the result. Use your right mouse button or Ctrl+c. In some browsers you can save the code in the textarea to a file with this button